OK, a very weird problem: I'm connecting a PS4 and Xbox One (S) to both a BENQ projector and an LG TV via the two outputs on a Denon Receiver. There is a (necessary) long cable run (15m) from Denon to TV, and shorter to the projector (5m). I get picture dropouts on the projector when using either source EXCEPT when the tv is either turned on, OR (and here's the weird part), when the TV mains cables is unplugged and then plugged in again. Another source (a Zappiti box) work fine and doesn't show this behaviour. I don't think its an HDMI ground loop problem as everything is now running off the same extension cable, but the behaviour when unplugging and then plugging in the TV again is pretty baffling to me. (and, in full disclosure, I'm a Professor in Electronic Engineering!). It's as if changing the grounding somehow shorts some charge in the TV which then fixes the issue in the projector, which then returns over a few hours or so. Banging my head against the wall on this one, any help or thoughts much appreciated.